It has now been found that, with an apparatus of the above-mentioned type, the liquid being fed in small amounts to the tubular tank or tanks carrying the flexible braids, is not evenly distributed across the several braids. More specifically, the portions of the braids or wicks which are facing the liquid inlets receive much more liquid than the portions lying further from these inlets, particularly those portions close to the ends of a tubular tank. As a consequence, the result expected from these prior devices is not sufficiently achieved.
On another hand, the solution which consists in providing external spray nozzles, such as described in the aforesaid European Patent and illustrated in FIG. 4 thereof, while improving the even distribution of the weed-killer liquid, offers this serious drawback that it tends to produce a mist which is liable to spread beyond the path of the braids so that it may affect the plants which are to be protected.
It is an object of this invention to provide improvements in devices of the above-mentioned type, for overcoming the above-stated drawbacks.